Continuous filament textile yarns

Jets for continuous filament textile yarn are typically 1-cm-diameter gold-platinum alloy structures with 20-500 holes of 50-200-/am diameter. Tire yarn jets are also 1 cm in diameter but typically use 1000-2000 holes to give the required balance of filament and yarn denier. Staple fiber jets can have as many as 70,000 holes and can be made from a single dome of alloy or from clusters of the smaller textile or tire yarn jets. The precious metal alloy is one of the few materials that can resist the harsh chemical environment of a rayon machine and yet be ductile enough to be perforated with precision. Glass jets have been used for filament production, and tantalum metal is a low cost but less durable alternative to gold-platinum. 

Polypropylenes are available as molding powder, extruded sheet, cast film, textile staple, and continuous-filament yarn. They find use in packaging film molded parts for automobiles, appliances, and housewares wire and cable coating food container closures bottles, printing plates carpet and upholstery fibers storage battery cases crates for soft-drink bottles laboratory ware trays fish nets surgical casts and a variety of other applications. 

Fig. 12.2. Force-elongation curves of manufactured textile continuous-filament yarns at standard conditions of 70°F and 65 percent relative humidity.

Available forms (Molding powder) Extruded sheet, cast film (1-10 mils), textile staple and continuous filament yarn, fibers with diameters from 0.05 to 1 p,m, and fiber webs down to 2 microns thick, low-density foam. 

Polyurethane fibers are another niche application. These elastanes, the basis of Lycra , have nearly taken over the textile industry, displacing rubber threads (elastodienes) in the process. The high popularity of PU fibers is attributable to the good tensile strength and elasticity of highly segmented polyurethanes. In addition, elastanes can be processed in a variety of sizes, either as continuous filaments (yarns) or as shorter fibers. Rubber threads, on the other hand, are available solely as monofilaments. ... 

Vinyon N is a continuous-filament yarn and Dynel is a staple fibre both are copolymers composed of 60 per cent vinyl chloride and 40 per cent acrylonitrile. These fibres are considerably more stable towards heat commencing to shrink at 116°C, and softening in the region of 130°C when shrinkage becomes marked. Dynel finds textile application because it has adequate stability towards heat, an extremely soft handle and is cheaper than the acrylics. 

ISO 1888. 1979 Textile glass Determination of the average diameter of staple fibres, or continuous filaments constituting a textile glass yarn—Cross section method. 

Fiber, staple Staple fibers are made up of a very large number of discontinuous, randomly oriented, individual fibers normally shipped in a box or bale. The fibers can be obtained by cutting continuous filament into V2 to 2 in. (12.7 to 50 mm) lengths and 1 to 5 denier or manufactured directly into desired lengths. They are usually subjected to a series of processes, culminating in textile spinning to yarn and are processed like natural fibers, such as wool and cotton, with which they can be blended. 

Nonwovens The textile and paper industries are based on the two oldest (wet and dry) processes. Manufacturers of nonwovens for plastics draw on both. With the wet, there are basically two types namely the Fourdrinier and cylinder machine types that have been modified. In addition, two basic types exist for the process formation of the web and application of the bonding agent or system where mechanical carding of fibers is used. The particular equipment and method of operation to be used, with their many modifications, is influenced by desired requirements such as mechanical properties, softness, surface condition, tenacity, etc. There are certain t) es of so-called nonwoven fabric that are directly formed from short or chopped fiber as well as continuous filaments. They are produced by loosely compressing together fibers, yarns, rovings, etc. with or without a scrim cloth carrier assembled by mechanical, chemical, thermal, or solvent methods. Products of this type include melted and spun-bonded fabrics. 

The viscose obtained from Cross and Bevan was so successful for production of lamp filaments that Steam asked Topham to try to spin it for use in textiles. The first experiments failed dismally. After several years of painstaking work, Topham made several discoveries essential to the spinning of yam from viscose aging (ripening) of the solution, filtration to remove particles, multiple-hole platinum spinnerettes, and a circular, centrifugally operated yarn collecting device that twisted the yam and packaged it in convenient cake form [117]. The Topham box, as it is still called, or variations of it are still on many of the continuous-filament rayon machines today. 

The largest commercial volume of these materials is in the form of fibers. Continuous filament yarns are preferred where very high mechanical properties are required and staple fiber is used for textile applications. The significant volumes involved in these applications led to the development of special spinning processes designed to produce these forms. 

Textile glass—Continuous filament yarns, staple fibre yarns, textured yarns and rovings (packages)—Determination of linear density Textile glass—Yarns—Designation... 

Denier per filament (DPF) fi-l9-m9nt n. The denier of an individual continuous filament or an individual staple fiber if it were continuous. In filament yarns, it is the yam denier divided by the number of filaments. Joespeh ML (1986) Textile science, 5th edn. CBS College Publishing, New York. 

Keywords use, application, chemical fiber, polypropylene fiber, monofilament, multifilament, staple fiber, tapes, spunbond, melt blown, split film, textile yarn, knitted fabrics, clothing, nonwoven fabric, home textiles, upholstery, geotextiles, agrotextiles, composites, medical textiles, automotive textiles, bulk continuous filaments (BCF), Eco-textiles, integrated fabric. 

The above fibre reinforcements are available in several forms that include almost parallel bundles of continuous filaments, either untwisted (rovings) or twisted (yarns), and short fibres (chopped) with a length of 3 mm to 50 mm (Keller, 2003). For use in pultrusion, fibre reinforcements can be worked to obtain textile products with several reinforcing directions. There are, therefore, several products available, either with randomly oriented fibres, which can be short (chopped strand mat) or continuous (continuous strand mat), or with oriented reinforcements (such as woven and non-woven fabrics, stitched fabrics, grids and meshes), which can be biaxial (0°/90° or -i-45°/-45°) or triaxial (0°/-i-45°/ 5°), the latter being considerably more expensive and less widely used in pultrusion. All these forms can be further combined to make complex textile products with continuous oriented fibres, together with randomly oriented short or continuous fibres. Figure 9.1 shows examples of forms of fibre reinforcement. 

Nonwovens are structures of textile materials, such as fibres, continuous filaments, or chopped yarns of any nature or origin, that have been formed into webs by any means, and bonded together by any means, excluding the interlacing of yams as in woven fabric, knitted fabric, laces, braided fabric or tufted fabric. 

The production machines can be normal spin-draw winders, as for the other melt-spun fibers. But here also, compact machines have been developed, for example for bulked continuous filament yarn (BCF, for carpet) with all the process steps on one machine, at an end speed of <1000 m min h Polypropylene is small in textile applications (in sportswear) but it has a reasonable position in high-tenacity yarns, in low-temperature applications such as ropes, cables, and geotextiles. It should be added that polypropylene can be drawn to high ratios (see Section 17.7.2). This results in very good tenacities, but the helix configuration of the isotactic chain in the crystals severely limits the modulus. 

Often continuous filament fibers require some type of bulk or twist before they can be used in textile applications. This is accomplished in carpet yarns generally produced from nylon 6, nylon 66 or polypropylene by using a BCF machine (Oerlikon Textile GMBH and CO., 2011). These lines are similar to the one-step fiber lines described above, except that the spinning speed... 

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